The thinner iS86 and it's update/s iS80 are definitely going to be a better ride for lighter riders in short sharp chop.... the control (and thus top end ability and general fun factor) are noticeably better on these later designs.... iS76 is pretty fast for bigger guys sailing hard and locked down committed, but has proven to be less confident/natural/comfortable with a lot of the lighter riders who have used the 76.